But they're not the only ones using social media to sound a digital alarm when disaster strikes. Officials in the U.S. do that too.

The U.S. Geological Survey (USGS), a scientific agency of the U.S. government, is tasked in part with researching natural disasters and getting the word out when they hit. They're doing much of that information sharing online. Scott Horvatt, Web and Social Media Chief at the USGS, says the organization uses a combination of Facebook and Twitter to spread information about “any significant earthquake event.”

@UGSGted tweets are sent out with the hashtag #quake. Once they're tweeted, Horvatt's system monitors tweets per minute with that hashtag. TED tweets are also automatically picked up and retweeted by the main @USGS account to its more than 186,000 followers.

Next, Horvatt and the USGS start crowdsourcing and responding to followers' questions. They send out a “Did You Feel It?” message with a link to a form that collects first-hand reports of major earthquakes, helpful to seismologists while they turn raw data into plain English. Gerber says his team tries to respond as quickly as possible to questions during and after a quake.

On Facebook, the USGS cross-posts all earthquake information it tweets along with the same “Did You Feel It?” links. That's breaking one of the first rules of social media (don't cross-post), but in the case of emergencies, it's best to get information out on all channels.

The USGS system isn't limited to the United States. Through an international partnership called the <AHREF="Global Seismographic Network, the USGS can learn and distribute information about events across the world.

Is the USGS planning any kind of social media-based early warning system? Not at the moment, says Horvatt. But social media does give the USGS a leg up when scouting for seismic trouble. By monitoring social chatter about a possible earthquake, Horvatt's team can alert seismologists to focus in on what may be happening in a certain geographic area.

“One of the goals behind the @USGSted account is that we have seismometers placed around the country, and in some areas they're less dense in terms of numbers,” says Horvatt. “The account lets us measure and take a look at the number of tweets coming across about an earthquake. It has the potential to give a bit of heads-up about something possible happening, but it's not meant as an early warning detection system.”

What do you think the future holds for social media and disaster alert systems? Sound off in the comments below.